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1.
Our aim is to compare short tone burst (STB)—and clicks—stimuli to evoke vestibular-evoked myogenic potentials (VEMPs) in healthy controls. A cross-sectional study in which VEMPs were measured in two sets of 185 and 55 normal volunteers by an air-conducted 500?Hz STBs and clicks, respectively. The test–retest reliability between different sessions was assessed in two subsets of 35 individuals. Moreover, 53 individuals were examined with both stimuli within the same session. Intraclass correlation coefficients (ICC) were used to assess reliability for P1 and N1 latencies, corrected amplitude and asymmetry ratio (AR). The results included that STBs produced a reliable response between different sessions (N?=?35; [ICC]?=?0.61–0.94, all p?<?0.0001). Although clicks produced a reliable response for P1 and N1 latencies and corrected amplitudes (ICC?=?0.62–0.74, all p?<?0.0001), the amplitude ratio showed a lower reliability [ICC?=?0.32 (?0.10 to 0.59)]. The amplitude of VEMP was consistently larger with 500?Hz STBs than clicks for a given sound pressure level. Within the same session, STBs evoked a response in 52/53 subjects (98%) whereas clicks evoked VEMPs only in 44/53 individuals (83%). Conclusions revealed that a 500?Hz STBs elicited consistently larger amplitudes, better reliability across recording sessions and fewer missing responses compared with click-induced VEMPs.  相似文献   
2.
The main purpose of the present meta-analysis was to examine the criterion-related validity of the 20-m shuttle run test for estimating cardiorespiratory fitness. Relevant studies were searched from twelve electronic databases up to December 2014, as well as from several alternative modes of searching. The Hunter-Schmidt’s psychometric meta-analysis approach was conducted to estimate the population criterion-related validity of the 20-m shuttle run test. From 57 studies that were included in the present meta-analysis, a total of 78 correlation values were analyzed. The overall results showed that the performance score of the 20-m shuttle run test had a moderate-to-high criterion-related validity for estimating maximum oxygen uptake (rp = 0.66-0.84), being higher when other variables (e.g. sex, age or body mass) were used (rp = 0.78-0.95). The present meta-analysis also showed that the criterion-related validity of Léger’s protocol was statistically higher for adults (rp = 0.94, 0.87-1.00) than for children (rp = 0.78, 0.72-0.85). However, sex and maximum oxygen uptake level do not seem to affect the criterion-related validity values. When an individual’s maximum oxygen uptake attained during a laboratory-based test is not feasible, the 20-m shuttle run test seems to be a useful alternative for estimating cardiorespiratory fitness. In adults the performance score only seems to be a strong estimator of cardiorespiratory fitness, in contrast among children the performance score should be combined with other variables. Nevertheless, as in the application of any physical fitness field test, evaluators must be aware that the performance score of the 20-m shuttle run test is simply an estimation and not a direct measure of cardiorespiratory fitness.

Key points

  • Overall the 20-m shuttle run test has a moderate-to-high mean criterion-related validity for estimating cardiorespiratory fitness.
  • The criterion-related validity of the 20-m shuttle run test is significantly higher for adults than for children. However, when the performance score is combined with other variables, the criterion-related validity value increases considerably among children.
  • Sex and maximum oxygen uptake level of individuals seem not to affect the criterion-related validity of the 20-m shuttle run test.
  • When individuals’ maximum oxygen uptake attained during a laboratory-based test is not feasible, the 20-m shuttle run test seems to be a useful alternative for estimating cardiorespiratory fitness.
Key words: Maximum oxygen uptake, peak oxygen uptake, PACER, Multistage fitness test, Léger test  相似文献   
3.
The main purpose of the present study was to examine the effects of a physical education-based stretching development and maintenance program on hamstring extensibility in schoolchildren. A sample of 150 schoolchildren aged 7-10 years old from a primary school participated in the present study (140 participants were finally included). The six classes balanced by grade were cluster randomly assigned to the experimental group 1 (n = 51), experimental group 2 (n = 51) or control group (n = 49) (i.e., a cluster randomized controlled trial design was used). During the physical education classes, the students from the experimental groups 1 and 2 performed a four-minute stretching program twice a week for nine weeks (first semester). Then, after a five-week period of detraining coinciding with the Christmas holidays, the students from the experimental groups 1 and 2 completed another stretching program twice a week for eleven weeks (second semester). The students from the experimental group 1 continued performing the stretching program for four minutes while those from the experimental group 2 completed a flexibility maintenance program for only one minute. The results of the two-way analysis of variance showed that the physical education-based stretching development program significantly improved the students’ hamstring extensibility (p < 0.001), as well as that these gains obtained remained after the stretching maintenance program (p < 0.001). Additionally, statistically significant differences between the two experimental groups were not found (p > 0.05). After a short-term stretching development program, a physical education-based stretching maintenance program of only one-minute sessions twice a week is effective in maintaining hamstring extensibility among schoolchildren. This knowledge could help and guide teachers to design programs that allow a feasible and effective development and maintenance of students’ flexibility in the physical education setting.

Key points

  • A physical education-based stretching maintenance program of only one-minute sessions twice a week is effective in maintaining hamstring extensibility among schoolchildren.
  • A four-minute maintenance program shows similar effects that the one-minute maintenance program on hamstring extensibility among schoolchildren.
  • Physical education teachers and other practitioners could carry out one-minute programs for a feasible and effective maintenance of students’ flexibility.
Key words: Flexibility program, flexibility maintaining, classic sit-and-reach test, physical fitness, primary school children, physical education setting  相似文献   
4.
BACKGROUND: To assess a possible role of systemic inflammation in the resting metabolic response in AIDS patients with active secondary infections. METHODS: Fifty-two patients with AIDS-defined criteria and concomitant active infections and 19 healthy subjects were studied. Measurements were as follows: body composition assessed by bioelectrical impedance; resting energy expenditure (REE) by 30-minute indirect calorimetry; cytokine concentrations (IL-6, IFNalpha, TNFalpha, sTNF-R1) by ELISA; C-reactive protein (CRP), erythrocyte sedimentation rate, fibrinogen, and nutritional parameters by standard techniques. RESULTS: REE adjusted for fat-free mass (REEFFM) was significantly increased in AIDS patients despite 39% of them not being hypermetabolic. The patients were undernourished and were found to have increased levels of acute-phase proteins and increased concentrations of IL-6 and sTNF-R1 relative to controls. REE parameters were positively related to CRP, ESR, ferritin, IL-6, and sTNF-R1 and negatively related to albumin, prealbumin, and transferrin. CRP was an independent predictor of REEFFM in AIDS patients and explained 25% of its variability. Patients with severe inflammation (CRP > or = 37 mg/dL) were significantly hypermetabolic with respect to patients without inflammation (CRP < 6 mg/dL) and had higher levels of IL-6 and sTNF-R1 and lower levels of albumin and prealbumin. Although no significant differences were observed with respect to the infection type, patients with tuberculosis and Pneumocystis carinii infections had higher resting metabolic and inflammatory responses, whereas patients with recurrent bacterial pneumonia were normometabolic and had lower levels of inflammatory markers. CONCLUSIONS: Resting hypermetabolism observed in AIDS patients with concurrent active infections is related to the presence and severity of systemic cytokine-driven inflammatory response, which could reflect the type of secondary infection.  相似文献   
5.
OBJECTIVES: To describe social inequalities in mortality in Seville from 1994 to 1998 according to socioeconomic status. METHODS: Life expectancy, crude and age-adjusted rates of total mortality as well as mortality by causes and potential years of life lost were estimated using the number of deaths and the population of Seville, aggregated by Basic Health Areas (BHA). BHA were divided in three levels according to the unemployment rate among men. The relative risks of total mortality and mortality by causes were estimated for men and women in each of these levels, using Poisson regression. The unemployment rate of each of the BHA was related to total mortality and to some of its causes. RESULTS: Differences in life expectancy of up to 7.9 years for men and 4.6 years for women were found among BHA. Concerning potential years of life lost, the areas with the highest mortality showed 4.1 times greater mortality in men and 2.6 times greater mortality in women than those with the lowest mortality. Total mortality increased with unemployment rate: the BHA with the highest unemployment rate showed a 15% increase in mortality in men and a 6% increase in that in women than those with the lowest unemployment rate. Among causes of mortality, AIDS showed the greatest inequalities in both men and women. CONCLUSIONS: From 1994 to 1998, Seville presented inequalities in total mortality and premature mortality, as well as in mortality by causes per BHA. Inequalities were present in men and women, although they were greater in men. There was a clear association between socioeconomic variables and mortality.  相似文献   
6.
BACKGROUND: Administration of antiretroviral therapy (ART) once daily is creating extraordinary interest among the members of the scientific community and also among those who receive the therapy. However, in clinical practice, some doubts remain about its use. OBJECTIVES: This document examines the characteristics and possibilities of treatment administered once daily. METHODS: Consensus of 248 Spanish experts in the field. RESULTS: Once-daily dosing is considered an added value which could favour adherence and, therefore, efficacy, as well as the quality of life of certain patients, however, the objective of adequate adherence in the long term is often difficult to achieve regardless of the treatment used. In theory, any patient can receive once-daily therapy, although some patients could particularly benefit from it, e.g. those with unfavourable social or personal circumstances, including drug users, patients whose treatment must be supervised, patients receiving multiple medications, or those who need rescue therapy after multiple treatment failures. At present, it is possible to design once-daily ART using some of the combinations of drugs considered as first-choice in national and international recommendations for antiretroviral therapy, but the options are still limited. The marketing of new drugs with this characteristic could allow us to increase the number and types of patient who can benefit from once-daily regimens, including those patients who need rescue therapy. CONCLUSIONS: Once-daily ART is a good alternative to regimens administered several times each day when a potent combination of active drugs is available.  相似文献   
7.
The effect of simultaneous plasma concentrations of pegylated interferon-alpha-2a (pegIFN-alpha-2a) and ribavirin (Rbv) on viral response has not been addressed to date. Hepatitis C virus (HCV)/human immunodeficiency virus (HIV)-coinfected patients received pegIFN-alpha-2a and Rbv under routine clinical care conditions. Plasma concentrations of the two drugs were measured using enzyme-linked immunosorbent assay and high-performance liquid chromatography after 2, 4, 8, and 12 weeks and at the end of the treatment period (24-48 weeks, according to HCV genotype and treatment duration). Large interindividual variability was observed in the plasma levels of both drugs. After multivariate analysis, only HCV genotype 3, low HCV-RNA levels, and pegIFN-alpha-2a exposure remained as independent factors associated with sustained viral response (SVR). The probability of attaining an SVR in HCV genotypes 1 and 4 was more than three to four times higher in patients with pegIFN-alpha-2a levels above the selected cutoff point. Early therapeutic drug monitoring of pegIFN-alpha-2a levels could be beneficial in improving current treatment outcomes.  相似文献   
8.
9.
BACKGROUND: Improvement of population health is the main aim and an important challenge for the health system. To monitor the population health indicators like disability-free life expectancy (DFLE) have been implemented. The purpose of this paper was to analyze the geographical distribution of DFLE according to autonomous regions in Spain. METHODS: Data of mortality, population and disability for the year 1999, provided by the National Institute of Statistics (INE), were used. To calculate DFLE by gender and region we used the Sullivan method that weights the expected time to live according to the status of disablement of the population. The standard error of DFLE, the expectation of disability and the proportion of time lived free of disability have also been estimated. RESULTS: In 1999 the DFLE at birth in Spain was 68.5 year for men and 72.2 years in women. Men lived proportionally more time free of disability than women (91% versus 87.7%) with an expectation of disability of 6.8 and 10.1 years respectively. Variability among regions was higher in DFLE than in life expectancy (LE). The regions with highest LE are not always those with the highest proportion of time lived without disability. CONCLUSIONS: Highest life expectancy does not always mean best health as it has been assumed currently. The DFLE indicator is a useful tool to show health status differences among the Spanish population.  相似文献   
10.
While hepatitis C virus (HCV) infection seems to be expanding among HIV‐infected men who have sex with men (MSM), the rate of coinfection in intravenous drug users (IDU) is assumed to remain constant. We evaluated the serial prevalence of HIV/HCV coinfection across all risk groups for HIV infection in Spain. We used data from 7045 subjects included in the multicentre, prospective Spanish Cohort of Adult HIV‐infected Patients (CoRIS) between 2004 and 2011. We analysed risk factors for HIV/HCV coinfection by logistic regression analyses. The prevalence of HIV/HCV coinfection decreased from 25.3% (95% CI, 23.1–27.5) in 2004–2005 to 8.2% (95% CI, 6.9–9.5) in 2010–2011. This trend was consistently observed from 2004 to 2011 among all risk groups: IDU, 92.4% to 81.4%; MSM, 4.7% to 2.6%; heterosexual men, 13.0–8.9%; and heterosexual women, 14.5–4.0% (all < 0.05). Strongest risk factors for HIV/HCV coinfection were IDU (OR, 54.9; 95% CI, 39.4–76.4), birth decade 1961–1970 (OR, 2.1; 95% CI, 1.1–3.7) and low educational level (OR, 2.4; 95% CI, 1.6–3.5). Hence, the prevalence of HIV/HCV coinfection decreased in Spain between 2004 and 2011. This decline was observed across all risk groups and is likely to be explained by a declining burden of HCV in the general population.  相似文献   
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